Children under 5 are major carriers of the coronavirus, study finds
- The severity and risk of Covid-19 in young children has been a hotly debated topic
- New research has shown high levels of viral material in children younger than five
- It’s, however, not yet certain to what extent young children may infect others
As Covid-19 progresses, one thing is certain – science moves quickly and new discoveries about the virus are made almost daily.
A hot Covid-19 debate included the extent to which children can spread the virus and whether schools should close to curb the spread, not only in South Africa, but also in the USA and UK.
A recent Health24 article discussed research that revealed that children between 10 and 19 are more likely to spread Covid-19 in their households than younger children. There were various hypotheses as to why younger children do not spread Covid-19 as rapidly as their older counterparts.
Early in the outbreak, research also revealed that children are more likely to develop milder Covid-19 and that the risk increases with age. Yet, there was no data as to what extent young children are able to spread the virus.
Now, new research published in JAMA Pediatrics reports that the replication of the SARS-CoV-2 virus in older children leads to similar levels of viral nucleic acid as in adults, but that these viral nucleic acids are even higher in five-year-old children.
What does it mean?
Viral nucleic acids refer to the amount of viral material present in the body, should the virus get a foothold. When a child younger than five is infected with SARS-CoV-2, the virus that can lead to the disease Covid-19, they may show mild symptoms or even be asymptomatic, while still carrying a large amount of viral material – up to 100 times more than adults – in their noses and throats.
The cohort study included subjects younger than a month up to the age of 65 who all tested positive for SARS-CoV-2. The researchers analysed their nasal swab samples to reveal the amount of nucleic acid present.
The authors state that this does not necessarily mean that children younger than five are more capable of passing the virus on to others, but suggest that the findings could influence the debate over the reopening of schools.
“The school situation is so complicated – there are many nuances beyond just the scientific one,” stated study leader Dr Taylor Heald-Sargent, a paediatric infectious disease expert at the Ann and Robert H. Lurie Children’s Hospital of Chicago. The study was published in JAMA Pediatrics and reported on by the New York Times.
Dr Heald-Sargent also said that, based on this research, we now know that simply because young children generally don’t get severe Covid-19, we shouldn’t assume that they don’t have the virus.
How will the research impact the future of Covid-19 and school regulations?
While experts are still unsure to what extent young children may spread the virus in their communities, they could potentially be drivers of the spread of SARS-CoV-2 in society.
It should also be mentioned that the study had its limitations. It was a small cohort study of only 145 patients and made no mention of underlying conditions, ethnicity or gender. The researchers also investigated viral RNA, which could be any genetic piece of the coronavirus, rather than the live virus.
Yet, the study is significant enough for experts to take heed.
“I’ve heard lots of people saying, ‘Well, kids aren’t susceptible, kids don’t get infected.’ And this clearly shows that’s not true,” said Stacey Schultz-Cherry, a virologist at St. Jude Children’s Research Hospital to the New York Times.
According to the researchers, this study suggests that the behavioural habits of young children, as well as the close proximity in schools and daycare centres, may raise concern about the virus spreading. They also suggest that immunisation should focus on the young as well, should a vaccine become available.
Image credit: iStock